Abstract: Embodiments of three-dimensional (3D) memory devices and methods for controlling a photoresist (PR) trimming rate in the formation of the 3D memory devices are disclosed. In an example, a method includes forming a dielectric stack over a substrate, measuring a first distance between the first trimming mark and the PR layer along a first direction, and trimming the PR layer along the first direction. The method also includes etching the dielectric stack using the trimmed PR layer as an etch mask to form a staircase, forming a second trimming mark using the first trimming mark as an etch mask, measuring a second distance between the second trimming mark and the trimmed PR layer, comparing the first distance with the second distance to determine a difference between an actual PR trimming rate and an estimated PR trimming rate, and adjusting PR trimming parameters based on the difference.

Abstract: Embodiments of source structure of a three-dimensional (3D) memory device and method for forming the source structure of the 3D memory device are disclosed. In an example, a NAND memory device includes a substrate, an alternating conductor/dielectric stack, a NAND string, a source conductor layer, and a source contact. The alternating conductor/dielectric stack includes a plurality of conductor/dielectric pairs above the substrate. The NAND string extends vertically through the alternating conductor/dielectric stack. The source conductor layer is above the alternating conductor/dielectric stack and is in contact with an end of the NAND string. The source contact includes an end in contact with the source conductor layer. The NAND string is electrically connected to the source contact by the source conductor layer. In some embodiments, the source conductor layer includes one or more conduction regions each including one or more of a metal, a metal alloy, and a metal silicide.

Abstract: A method for processing IC designs for different metal BEOL processes is provided for enabling fabricating using a metal fabrication process an IC originally having a backend design for a different metal fabrication process. The method first determines layer constructions of an original design of an IC for a first metal backend process, and, based on the layer constructions of the original design of the IC, constructs primitive layer constructions of a target design of the IC for a second metal backend process. The method then tunes an effective dielectric constant of a dielectric layer of the target design to match an associated capacitance of the target backend design with a corresponding capacitance of the original backend design. The method can be used to convert a backend design of an IC from an old metal process (such as Al process) to a new metal process (such as Cu process), without redesigning the IC for the new metal BEOL fabrication process.

Abstract: A semiconductor fabrication method or process is provided for fabricating an integrated circuit (IC) originally having an Al backend design using a Cu BEOL fabrication process. The method converts the Al backend design to a Cu backend design without redesigning the IC for Cu BEOL fabrication process, and uses the resultant Cu design to fabricate the IC using Cu BEOL fabrication process. The Al-Cu conversion first determines layer construction of the Al design, and then matches metal resistances of the Al design with metal resistances of a Cu design, matches intra-metal capacitances of the Al design with intra-metal capacitances of the Cu design, and matches inter-metal capacitance of the Al design with inter-metal capacitances of the Cu design.